This invention relates to improved means for the chute feeding of fibrous flock to carding machines, which means substantially reduces the "working" of the constituent staple fibers from what previously was known.
Staple fibers useful in textile end uses usually are received by commercial textile mills in a baled form. The bales then are opened and the fibers are removed therefrom in the form of clusters of fibrous flock by some device such as a bale opener machine, or bale discintegrator machine or the like. The flock clusters then are moved, usually by air flow as in the chute feed method, to a feeder device which feeds the fibers to a carding machine in the form of a somewhat compacted batt of fibers. The form of the batt and also of the individual fibers of the batt often determine the quality provided to the end product of the textile use process, usually a yarn to form woven or knit textile goods, or a nonwoven web. Uniformity of density of the batt is a desired goal. Also, providing constituent fibers in the least stressed form, which is to say fibers which have been subjected to the least amount of imposed stress possible, is another highly desired goal.
However, until the advent of this invention, fibers conveyed to carding machines by the chute feed method have invariably been subjected to severe, imposed stress. Often such stress causes the formation of hook-like ends to the individual staple fibers causing all manner of subsequent processing problems and reduced product quality. Yet other problems include a tendency for greater non-uniformity of properties in the end textile product.
It is to the assuagement of these problems to which the present invention is directed, such being an object thereof.
In the prior art of chute feeding, the fibrous flock received from the bale opener device via air currents enters the vertical fiber receiving chute to form a column therein. The column is supported at the bottom of the receiving chute by a horizontally disposed feed roller axially supported for rotational movement within a cup-like bottom channel of the receiving chute, the bottom of the cup being a somewhat restricted opening. The bottom wall portions of the cup-like channel are curved inwardly in spaced away relation to the surface of the feed roller to form a passageway for the flock being moved by the feed roller in its rotation. This passageway terminates in the aforesaid restricted opening, which latter communicates with the downwardly depending feed channel chute by way of a guide channel bounded by a guide wall and the surface of a beater roller. The beater roller is mounted or nests such that its rotational axis is substantially parallel to that of the feed roller and spaced away therefrom a sufficient distance that the beater ribs or vanes terminate at and intrude into the aforesaid restricted opening at the bottom of the receiving chute.
In operation, the feed roller receives flock from the bottom of the column in which it is in contact, and moves the flock by its rotation to and through the restricted opening. The beater roller, which is invariably rotated in the same rotational sense as the feed roller, receives flock entering the restricted opening thereabove and its vanes rotate the stock therewith. In so doing the fibrous stock is pressed strongly and sharply about the walls of the restriction of the bottom cup opening, subjecting the constituent fibers to high shear and pulling stresses before being dropped into the feed channel chute for subsequent delivery to the feed roll of a carding machine. The shear, bending and elongation stresses imposed upon the fibers by the aforementioned process produce fibers which are, in the art used expression, strongly "worked."